Qt5 cannot find header files - OpenSuse
This may be a regular question but so far I couldn't find an answer.
The following error appears when trying to compile:
g++ -c -m64 -pipe -O2 -Wall -W -D_REENTRANT -fPIE -DQT_NO_DEBUG -DQT_GUI_LIB -DQT_CORE_LIB -I../qtbase/mkspecs/linux-g++-64 -I. -I. -I../qtbase/include -I../qtbase/include/QtGui -I../qtbase/include/QtCore -I. -o a.o a.cpp
a.cpp:1:24: fatal error: QApplication: No such file or directory
This happens when I run with qmake -project --> qmake --> make. As well as from c++ directly:
fatal error: QApplication: No such file or directory
It cannot find any header, although they are all there in ../qtbase/include/ . It seems something with the configure, i.e., before the compilation, which by the way ran without errors.
The code I ran is the first in http://doc.qt.digia.com/4.7/gettingstartedqt.html#creating-a-pro-file
I appreciate any help.
Ran into the same problem. I think I've figured this out now. This solution is based on this "post":http://qt-project.org/forums/viewthread/23009 .
Apparently in Qt5 qtwidgets is a module which is apart from qtgui (in contrast to qt4). Therefore adding
@QT += widgets@
to your .pro file should do the job (it seems qmake is the culprit).
So to compile you would do something like
qmake -project -> (if needed, add "QT += widgets" to the .pro file) -> qmake -> make.
I've tried this on a couple of the qt examples and it has worked.
Hope it helps.